Surgical stapling device having supports for a flexible drive mechanism

ABSTRACT

A surgical stapler comprising a staple cartridge comprising a curved deck configured to support tissue is disclosed. The curved deck comprises an inner radius of curvature, an outer radius of curvature, a first step, and a second step. The staple cartridge further comprises a first longitudinal row of staple cavities, a second longitudinal row of staple cavities, and staples removably stored in the first and second longitudinal rows of staple cavities. The surgical stapler further comprises an anvil, a first camming member, a second camming member, a cutting member, a driver, and support means for supporting the driver when the driver moves the cutting member relative to the anvil and the staple cartridge.

CROSS REFERENCE TO RELATED APPLICATIONS

This non-provisional patent application is a continuation applicationunder 35 U.S.C. §120 and claims the benefit from U.S. patent applicationSer. No. 11/652,166, entitled SURGICAL STAPLING DEVICE HAVING SUPPORTSFOR A FLEXIBLE DRIVE MECHANISM, filed on Jan. 11, 2007, now U.S. Pat.No. 8,827,133, the disclosure of which is hereby incorporated byreference in its entirety.

The subject application is related to six commonly-owned applicationsfiled on Jan. 11, 2007, the disclosure of each is hereby incorporated byreference in their entirety, these six applications being respectivelyentitled:

(1) U.S. patent application Ser. No. 11/652,169, SURGICAL STAPLINGDEVICE WITH A CURVED CUTTING MEMBER, now U.S. Patent ApplicationPublication No. 2008/0169332;

(2) U.S. patent application Ser. No. 11/652,165, SURGICAL STAPLINGDEVICE WITH A CURVED END EFFECTOR, now U.S. Pat. No. 8,540,128;

(3) U.S. patent application Ser. No. 11/652,188, APPARATUS FOR CLOSING ACURVED ANVIL OF A SURGICAL STAPLING DEVICE, now U.S. Pat. No. 7,434,717;

(4) U.S. patent application Ser. No. 11/652,164, CURVED END EFFECTOR FORA SURGICAL STAPLING DEVICE, now U.S. Pat. No. 8,701,958;

(5) U.S. patent application Ser. No. 11/652,423, BUTTRESS MATERIAL FORUSE WITH A SURGICAL STAPLER, now U.S. Patent Application Publication No.2008/0169328; and

(6) U.S. patent application Ser. No. 11/652,170, SURGICAL STAPLER ENDEFFECTOR WITH TAPERED DISTAL END, now U.S. Patent ApplicationPublication No. 2008/0169333.

BACKGROUND

1. Field of the Invention

The present invention generally relates to surgical staplers, and, moreparticularly, to surgical staplers having a curved end-effector and tosurgical techniques for using the same.

2. Description of the Related Art

As known in the art, surgical staplers are often used to deploy staplesinto soft tissue to reduce or eliminate bleeding from the soft tissue,especially as the tissue is being transected, for example. Surgicalstaplers, such as an endocutter, for example, often comprise anend-effector which is configured to secure the soft tissue between firstand second jaw members. The first jaw member often includes a staplecartridge which is configured to removably store staples therein and thesecond jaw member often includes an anvil. In use, the staples aretypically deployed from the staple cartridge by a driver which traversesa channel in the staple cartridge. The driver causes the staples to bedeformed against the anvil and secure layers of the soft tissuetogether. Often, as known in the art, the staples are deployed inseveral staple lines, or rows, in order to more reliably secure thelayers of tissue together. The end-effector may also include a cuttingmember, such as a knife, for example, which is advanced between two rowsof the staples to resect the soft tissue after the layers of the softtissue have been stapled together.

The end-effectors of previous endocutters are often configured to deploystaples in straight lines. During many surgical techniques, such as theresection of stomach tissue, for example, such a linear deployment isoften preferred. During these techniques, the end-effector is typicallyinserted through a cannula to access the surgical site and, as a result,it is often desirable for the end-effector to have a linearconfiguration that can be aligned with an axis of the cannula before theend-effector is inserted therethrough. However, in some circumstances,end-effectors having such a linear configuration are somewhat difficultto use. More particularly, for example, when the end-effector must beplaced adjacent to or against a cavity wall, such as the thoracic cavitywall, for example, it is often difficult for the surgeon to position ajaw of the end effector behind delicate or fragile tissue which isproximal to and/or attached to the cavity wall. Furthermore, even if thesurgeon is successful in positioning a jaw behind the tissue, owing tothe linear configuration of the end-effector, the surgeon may not beable to see the distal end of the end-effector.

In some circumstances, endocutters having a curved end-effector havebeen used for accessing, stapling and transecting tissue. Theseend-effectors typically include curved anvils and staple cartridgeswhich co-operate to deploy the staples in curved rows. To deploy thestaples in this manner, the staple driver and the cutting member can bemoved through a curved path by a flexible drive member. However, owingto the amount of force that is typically transmitted through theflexible drive member, the drive member may buckle or otherwise deformin an unsuitable manner. Furthermore, previous curved end-effectors areconfigured such that the distal ends of the jaw members are the lastportions of the jaw members to contact the soft tissue. As a result,tissue may escape from between the jaw members before the jaw membersare completely closed. What is needed is an improvement over theforegoing.

SUMMARY

In various embodiments, the present invention includes a surgicalstapler having an end-effector which is configured to deploy staples inat least one staple line. In at least one embodiment, the surgicalstapler includes a staple cartridge configured to removably storestaples therein, an anvil configured to deform the staples, a cuttingmember having a cutting surface, and a driver operably engaged with thecutting member to move the cutting member relative to the anvil and thestaple cartridge. In at least one embodiment, one of the anvil and thestaple cartridge defines a slot which is configured to receive at leasta portion of the cutting member and guide the cutting member as it ismoved relative to the anvil and the staple cartridge. In theseembodiments, the slot can also be configured to receive a portion of thedriver operably engaged with cutting member and support the driver whenit moves the cutting member relative to the anvil and the staplecartridge. In at least one embodiment, the slot is defined by at leastone radius of curvature.

BRIEF DESCRIPTION OF THE FIGURES

The above-mentioned and other features and advantages of this invention,and the manner of attaining them, will become more apparent and theinvention itself will be better understood by reference to the followingdescription of embodiments of the invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 is a schematic of an endocutter being used to transect and stapletissue;

FIG. 2 is a partial cut-away view of the endocutter of FIG. 1;

FIG. 3 is a partial cross-sectional view of the endocutter of FIG. 2taken along line 3-3 in

FIG. 2;

FIG. 4 is a perspective cut-away view of the endocutter of FIG. 2;

FIG. 5 is a bottom view of the anvil of the endocutter of FIG. 2;

FIG. 6 is a schematic view of staples being deployed from the staplecartridge of the endocutter of FIG. 2 by a staple driver;

FIG. 7 is a schematic view of staples being deployed from the staplecartridge of FIG. 2 where the staple driver has been advanced within thestaple cartridge with respect to its position in FIG. 6;

FIG. 8 is a perspective view of the cutting member and drive bar of theendocutter of FIG. 2;

FIG. 9 is a schematic of an opened thoracic cavity;

FIG. 10 is a schematic of an endocutter having a curved end-effector inaccordance with an embodiment of the present invention being positionedagainst the side wall of a thoracic cavity;

FIG. 11 is a perspective view of the endocutter of FIG. 10 illustratedin a closed configuration and positioned about a pulmonary artery;

FIG. 12 is a perspective view of the end-effector of the endocutter ofFIG. 11;

FIG. 13 is a top view of the staple cartridge of the end-effector ofFIG. 12;

FIG. 14 is a bottom view of the jaw configured to support the staplecartridge of FIG. 13;

FIG. 15 is a perspective view of the cutting member and staple driver ofthe endocutter of FIG. 2;

FIG. 16 is a top view of the cutting member and staple driver of FIG.15;

FIG. 17 is a top view of a cutting member and staple driver inaccordance with an embodiment of the present invention;

FIG. 18 is a perspective view of an endocutter having a curvedend-effector in accordance with an alternative embodiment of the presentinvention;

FIG. 19 is a top view of the staple cartridge of the end-effector ofFIG. 18;

FIG. 20 is a perspective view of an endocutter having a curvedend-effector in accordance with an alternative embodiment of the presentinvention;

FIG. 21 is a top view of the staple cartridge of the end-effector ofFIG. 20;

FIG. 22 is a perspective view of an endocutter having a curvedend-effector in accordance with an alternative embodiment of the presentinvention;

FIG. 23 is a top view of the staple cartridge of the end-effector ofFIG. 22;

FIG. 24 is a cross-sectional view of the end-effector of FIG. 12 takenalong line 24-24 in FIG. 12;

FIG. 25 is a cross-sectional view of the end-effector of FIG. 12 afterthe drive bar has been advanced into the end-effector;

FIG. 26 is a schematic of the cutting member and drive bar of theendocutter of FIGS. 24 and 25;

FIG. 27 is a perspective view of an endocutter having a curvedend-effector configured to close in an asymmetric manner in accordancewith an embodiment of the present invention;

FIG. 28 is a cross-sectional view of the hinge connection between thejaws of the curved end-effector of FIG. 27 wherein the jaws are in anopen configuration;

FIG. 29 is a cross-sectional view of the hinge connection of FIG. 28wherein the jaws are in a partially closed configuration;

FIG. 30 is an end view of the curved end-effector of FIG. 27 illustratedin a partially closed configuration;

FIG. 31 is a cross-sectional view of the hinge connection of FIG. 28wherein the end-effector is in a closed configuration;

FIG. 32 is an end view of the curved end-effector of FIG. 27 illustratedin a closed configuration;

FIG. 33 is a detail view of a first slot of the hinge connection of FIG.28 that is configured to receive a first projection extending from theanvil and is also configured to define a first path for relativemovement therebetween;

FIG. 34 is a detail view of a second slot of the hinge connection ofFIG. 28 that is configured to receive a second projection extending fromthe anvil and is also configured to define a path for relative movementtherebetween that is different than the first path;

FIG. 35 is a perspective view of an endocutter having a curvedend-effector in accordance with an alternative embodiment of the presentinvention;

FIG. 36 is a side view of the endocutter of FIG. 35;

FIG. 37 is a schematic of the endocutter of FIG. 35 being used totransect a pulmonary artery;

FIG. 38 is a perspective view of an endocutter having a curvedend-effector in accordance with an alternative embodiment of the presentinvention;

FIG. 39 is a perspective view of the staple cartridge of theend-effector of FIG. 38;

FIG. 40 is a side view of the end-effector of the endocutter of FIG. 39;

FIG. 41 is a partial cross-sectional view of the end-effector of theendocutter of FIG. 38;

FIG. 42 is a perspective view of the staple driver, cutting member anddrive bar of FIG. 41;

FIG. 43 is a perspective view of the cutting member and drive bar ofFIG. 41;

FIG. 44 is a perspective view of an endocutter having a curved staplecartridge and a curved anvil configured to retain buttress materialthereon in accordance with an embodiment of the present invention;

FIG. 45 is a top view of the staple cartridge of FIG. 44 illustrating apiece of buttress material positioned thereon;

FIG. 46 is a bottom view of the anvil of FIG. 44 illustrating two piecesof buttress material positioned thereon;

FIG. 47 is a cross-sectional view of the end-effector of the endocutterof FIG. 44 taken along line 47-47 in FIG. 44;

FIG. 48 is a perspective view of an endocutter in accordance with anembodiment of the present invention;

FIG. 49 is a cross-sectional view of the end effector of FIG. 48 takenalong line 49-49 in FIG. 48; and

FIG. 50 is an enlarged cross-sectional view of the distal end of the endeffector of FIG. 49.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate preferred embodiments of the invention, in various forms, andsuch exemplifications are not to be construed as limiting the scope ofthe invention in any manner.

DETAILED DESCRIPTION

As known in the art, it is often necessary to resect tissue from apatient after the tissue has become necrotic or cancerous, for example.Frequently, blood vessels within the tissue are transected as the tissueis being cut. As a result, blood may flow from the blood vessels andcomplicate the surgery or endanger the patient. Often, a surgicalstapler is used to secure and compress several layers of tissue togetherin order to substantially close the blood vessels. For example,referring to FIG. 1, a surgical stapler, such as an endocutter, caninclude devices which staple and then cut the tissue. As a result, theblood vessels can be substantially closed by the staples before thetissue is cut, thereby reducing bleeding therefrom.

Referring to FIGS. 1 and 2, endocutters, such as endocutter 100, forexample, typically include an end-effector 102, a handle portion 104(FIG. 2), and a shaft 106 extending therebetween. End-effector 102includes first jaw 108 and second jaw 110 which can be configured in oneof an open or a closed configuration. In their open configuration, jaws108 and 110 can be configured to receive soft tissue therebetween, forexample, allowing jaws 108 and 110 to be placed on opposite sidesthereof. To close the jaws and secure the tissue therebetween, at leastone of the jaws is moved against the tissue such that it holds thetissue against the opposing jaw. In the illustrated embodiment, jaw 108is moved relative to jaw 110. Once closed, as known in the art, ananti-firing mechanism can be released allowing cutting member 120 to beadvanced toward the tissue. Thereafter, as described in greater detailbelow, staples 132 can be deployed from staple cartridge 112 in jaw 110to secure the layers of tissue together. Such mechanisms are describedin greater detail in U.S. Pat. No. 7,000,818, the disclosure of which ishereby incorporated by reference herein.

Referring to FIGS. 3-4 and 6-8, cutting member 120 includes body 122 andcutting surface 124. Cutting member 120 is operably engaged with firingtrigger 128 of handle portion 104 via drive bar 126 wherein theactuation of firing trigger 128 advances drive bar 126 and cuttingmember 120 toward the distal ends of jaws 108 and 110. In variousembodiments, firing trigger 128 can activate a firing drive system whichmay be manually, electrically, or pneumatically driven. Cutting memberbody 122 further includes distal portion 123 which is configured toengage a staple driver 130 commonly supported within staple cartridge112 and advance staple driver 130 therein. As staple driver 130 isadvanced, staples 132 are lifted by driver 130 toward anvil 134.Referring to FIG. 5, anvil 134 includes pockets 136 which are configuredto deform the legs of staples 132 and capture the layers of tissuetherein in a known manner. In the present embodiment, as staple driver130 is advanced, cutting member 120 is also advanced to resect thetissue after it has been stapled. In other embodiments, cutting member120 can be configured to resect the tissue during or before the tissuehas been stapled.

Referring to FIGS. 1-7, the end-effector of many typical endocutters islinear, i.e., it is configured to deploy staples in straight lines. Inthese endocutters, drive bar 126 is configured to move cutting member120 in a straight line and, accordingly, drive bar 126 is rigid suchthat it does not substantially deflect when the force to deploy thestaples and transect the tissue is transmitted therethrough. In additionto the above, a variety of other drive arrangements are known fordeploying staples in straight lines while resecting the tissue locatedbetween opposite lines of staples. However, it is often difficult toposition such linear end-effectors in a surgical site. During at leastone surgical technique, referring to FIGS. 9 and 10, an endocutter isused to transect and staple a pulmonary artery (PA) during a partial ortotal pneumonectomy. During this technique, the end-effector istypically placed against the wall of the thoracic cavity (TCW) such thatjaw 110, and staple cartridge 112, are positioned behind the pulmonaryartery. However, as the wall of the thoracic cavity is typically curved,it is often difficult to position linear jaw 110 behind the pulmonaryartery. Furthermore, even if the surgeon is successful in positioning ajaw behind the pulmonary artery, the surgeon, owing to the linearconfiguration of the end-effector, cannot readily see the end of the jawas it is typically hidden behind the pulmonary artery. As a result, itis difficult for the surgeon to readily determine whether the end of thejaw extends beyond the pulmonary artery, i.e., whether the pulmonaryartery is entirely captured between the jaws of the end-effector.

In various embodiments of the present invention, referring to FIG. 10,the end-effector of the endocutter is curved. A curved end-effectorallows a surgeon to more easily position the end-effector against thecurved wall of the thoracic cavity, for example. In at least oneembodiment, the curvature of the end-effector can be configured tosubstantially match the contour of a typical thoracic cavity wall. Inthese embodiments, the curvature of several thoracic cavity walls can bemeasured and statistically analyzed to determine the optimum profile ofthe curved end-effector. This profile can include several arcuateportions and, in addition, several linear portions. In otherembodiments, referring to endocutter 200 of FIGS. 10-14, the curvatureof the thoracic cavity wall can be approximated by a single radius ofcurvature. Such embodiments can be simpler and less expensive tomanufacture. In at least one embodiment, this radius of curvature is1.2″. In other various embodiments, the curvature of the end-effectorcan be configured to match the profile of the lower rectum, pelvis, orlower abdomen.

In order to transect the pulmonary artery PA, as mentioned above, asurgeon typically positions one of jaws 208 and 210 behind the pulmonaryartery PA against the thoracic cavity wall TCW. Once positioned,referring to FIGS. 10 and 11, closure trigger 117 is actuated to pivotjaw 208 with respect to jaw 210 such that anvil 234 contacts thepulmonary artery and compresses the pulmonary artery between anvil 234and staple cartridge 212. Unlike previous linear end-effectors, thecurved profile of end-effector 202 assists the surgeon in locating thedistal end of the end-effector with respect to the pulmonary artery.More particularly, referring to FIGS. 13 and 14, end 240 of jaw 210 canextend to one side of a centerline, or axis 242, defined by the distalend of shaft 106. As a result of this offset, the surgeon may be able tomore readily see distal end 240 and evaluate whether the pulmonaryartery is completely captured within the end-effector, for example.

Once the jaws of the endocutter have been closed, the cutting member ofthe endocutter can be advanced toward the tissue, as described above. Inprevious endocutters, referring to FIGS. 4, 15 and 16, cutting member120 is configured to travel within linear slots defined by staplecartridge 112, staple cartridge channel 138, and anvil 134. Similarly,staple driver 130 is configured to travel within at least one linearslot defined by staple cartridge 112. As a result of these linear slots,cutting member 120 and staple driver 130 are moved in a straight linebetween the proximal and distal ends of the end-effector. For example,referring to FIG. 4, cutting member 120 includes first projections 146extending from body 122 which are sized and configured to fit withinslot 148 of anvil 134. Cutting member 120 further includes secondprojections 150 extending from body 122 which are sized and configuredto retain cutting member body 122 within slot 164 of staple cartridge112 and slot 152 of jaw 110. Accordingly, as cutting member 120 isadvanced from the proximal end of the end-effector to the distal end,linear slots 148, 152 and 164 define a linear path for cutting member120.

In various embodiments of the present invention, referring to FIGS. 13and 14, staple cartridge 212, staple cartridge channel 238 and anvil 234can include curved slots for controlling the movement of cutting member120 and staple driver 130 along a curved path. These curved slots caninclude several arcuate portions and several linear portions. In variousembodiments, the curved slots can be defined by one radius of curvature.In the embodiment illustrated in FIGS. 13 and 14, staple cartridge 212and staple cartridge channel 238 can include curved slots 264 and 252,respectively. Similar to the above, curved slots 264 and 252 can beconfigured to receive a portion of cutting member 120 and guide cuttingmember 120 along a path defined by slots 264 and 252. However, owing tothe substantially linear configuration of cutting member 120, cuttingmember 120 may, in some circumstances, become misaligned or stuck withincurved slots 264 and 252, or a corresponding curved slot in anvil 234.

To ameliorate the above-described problem, at least a portion of thecutting member and staple driver can be curved. In at least oneembodiment, the cutting member and staple driver can be configured tosubstantially match the curvature of the path defined by curved slots264 and 252, i.e., path 258. More particularly, referring to FIGS. 13and 17, cutting member body 222 can include a center portion which isconfigured to match the radius of curvature of path 258, and a curvedinner portion 260 and a curved outer portion 262 which are configured toco-operate with the sidewalls of curved slots 264 and 252. For example,curved cartridge channel slot 252 can include inner surface 254 andouter surface 256 and curved staple cartridge slot 264 can include innersurface 266 and outer surface 268 where, in the present embodiment,inner surfaces 254 and 266 are substantially defined by radius ofcurvature D, which is smaller than the radius of curvature of path 258,and outer surfaces 256 and 268 are substantially defined by radius ofcurvature C, which is larger than the radius of curvature of path 258.As illustrated in FIG. 17, inner portion 260 of cutting member 220 canbe configured to closely parallel the profile of inner surfaces 254 and266, and outer portion 262 of cutting member 220 can be configured toclosely parallel the profile of outer surfaces 256 and 268. Furthermore,although not illustrated, anvil 234 can include a curved slot which,similar to slots 264 and 252, co-operates with curved cutting member 220to guide cutting member along path 258. As a result of the above, thelikelihood of cutting member 220 becoming misaligned or stuck withincurved path 252 can be reduced.

Alternatively, although not illustrated, the cutting member can includeslots which are configured to co-operate with features on the anviland/or staple cartridge and guide the cutting member along a curvedpath. More particularly, the anvil and/or staple cartridge can eachinclude an elongate, arcuate projection, or a plurality of projections,which define a curved, or curvilinear, path for the cutting member. Theslots of the cutting member can be configured to receive the projectionsand guide the cutting member along the curved path. In one embodiment,one of the anvil and staple cartridge can include such a projection, ora plurality of projections, and the other of the anvil and staplecartridge can include a slot configured to receive a portion of thecutting member, as described above.

Similar to the above, at least a portion of staple driver 230 can beconfigured to substantially match the curvature of path 258. Moreparticularly, referring to FIG. 17, staple driver 230 can include acenter arcuate portion 270 which is configured to match the radius ofcurvature of path 258, and an inner arcuate portion 272 and an outerarcuate portion 274 which are configured to co-operate with thesidewalls of slots, or channels, within staple cartridge 212. Similar tostaple driver 130, staple driver 230 can include ramps which areconfigured to lift, or deploy, staples 132 against anvil 234 positionedopposite staple cartridge 212. However, in the present embodiment, ramps276 of staple driver 230 can be curved to deploy staples 132 along acurved staple line. More particularly, for example, the ramps can bedefined by a radius of curvature which substantially matches the radiusof curvature of a staple line. For example, ramp 278 is defined by aradius of curvature which substantially matches the radius of curvatureof staple line 280, i.e., radius of curvature A.

Although the path of the cutting member has been described above asbeing defined by a single radius of curvature, the invention is not solimited. In various embodiments, referring to FIGS. 13 and 14,end-effector 202 of endocutter 200 can include curved portion 263 and,in addition, linear portion 261 which is substantially collinear with anaxis defined by the distal portion of shaft 116, i.e., axis 242. In atleast one embodiment, curved portion 263 can further include firstportion 265 and second portion 267. Referring to FIG. 13, first portion265 can include a proximal end connected to linear portion 261positioned along axis 242 and a distal end spaced from axis 242 whereinsecond portion 267 can include a proximal end connected to the distalend of first portion 265 and extend toward axis 242. Stated another way,first portion 265 can define an arcuate portion which extends away fromaxis 242 and second portion 267 can define an arcuate portion whichextends toward axis 242. As described above, an end-effector having sucha profile may facilitate the positioning of the end-effector against thewall of the thoracic cavity, for example.

Referring to FIGS. 18-21, the end-effector of other various embodimentsof the present invention can include other advantageous profiles. Forexample, referring to FIGS. 18 and 19, end-effector 302 can includelinear portion 361 and curved portion 363 wherein the distal end of slot364 can be positioned along axis 242. As a result, although the cuttingmember progresses along an arcuate path offset with respect to axis 242,the cutting member will stop at a point along axis 242. Thus, as long asthe surgeon is able to discern the orientation of axis 242, the surgeonwill know that the cutting member will not progress beyond axis 242 andcan thereby gauge the point at which the tissue will no longer betransected. In another embodiment, referring to FIGS. 20 and 21,end-effector 402 can include linear portion 461 and curved portion 463wherein distal tip 440 of the end-effector lies along axis 242 althoughat least a portion of the end-effector is offset with respect to axis242. In this embodiment, as long as the surgeon is able to discern theorientation of axis 242, the surgeon can gauge the location of thedistal end of the end-effector when moving or dissecting tissue.

In other various embodiments, referring to FIGS. 22 and 23, theend-effector can define an arcuate path for the cutting member that isdefined by an angle that is greater than or equal to 90 degrees. Moreparticularly, for example, path 558 can include linear portion 561 andcurved portion 563 wherein curved portion 563 is defined by a radius ofcurvature that spans an arc corresponding to an approximately 110 degreeangle. As a result of the significant curvature of curved portion 563, asurgeon can position a pulmonary artery, for example, entirely withincurved portion 563. In various embodiments, referring to FIG. 26,staples 132 may only be positioned within cavities in curved portion563, and not linear portion 561. In these embodiments, the staple linescan be comprised of continuous, curved rows without abrupt changes indirection within the staple line. As known in the art, abrupt changes ina staple line may provide a leak path for blood to flow therethrough. Asa result of the above embodiments, the likelihood of such a leak path isreduced.

As described above, the anvil and staple cartridge can include curvedslots for receiving and guiding the cutting member. In many embodiments,the anvil and the staple cartridge can be configured such that theirfeatures parallel the curved slots therein. For example, referring toFIGS. 13 and 14, curved portion 263 of staple cartridge 212 can includean inner radius of curvature and an outer radius of curvature whichparallel the radius of curvature of curved slot 264. More particularly,referring to FIG. 13, the inner surface of staple cartridge 212 can bedefined by radius of curvature E and the outer surface of staplecartridge 212 can be defined by radius of curvature B, whereincurvatures B and E share a substantially common radial point with radiusof curvatures C and D which, as described above, substantially definethe inner and outer surfaces of slot 264. However, in variousembodiments, although not illustrated, the inner and outer surfaces ofthe anvil and/or staple cartridge, or any other features thereof, may benon-parallel to the curved slot. In these embodiments, the anvil andstaple cartridge, and the jaws surrounding them, may be configured toachieve any suitable configuration or purpose.

In previous endocutters, as described above and referring to FIGS. 4 and8, linear drive bar 126 is configured to advance cutting member 120along a linear path and, as a result, drive bar 126 is constructed suchthat is rigid and does not substantially deflect. After cutting member120 has been advanced into slots 148, 164 and 152 of anvil 134, staplecartridge 112, and staple cartridge channel 138, respectively, at leasta portion of drive bar 126 can enter into slots 148, 164 and 152.However, although cutting member 120 is guided and supported withinslots 148, 164, and 152, drive bar 126, in these previous devices, isunsupported within slots 148, 164, and 152. As a result, drive bar 126may deflect or buckle in an uncontrollable and undesirable manner whenload is transmitted therethrough.

In various embodiments of the present invention, a flexible drive barcan be used to advance the cutting member within the end-effector. Moreparticularly, in order for the drive bar to be advanced into andtranslate within the curved slots of the end-effector, the drive bar candeflect to closely parallel the curvature of the curved slots of theend-effector. In various embodiments, unlike previous endocutters, theslots within the anvil and staple cartridge can be configured to supportthe flexible driver bar. More particularly, after cutting member 120 hasbeen at least partially advanced within slots 248, 264, and 252,referring to FIG. 25, at least a portion of drive bar 226 can enterslots 248, 264, and 252. Slot 248 can include support surfaces 249 whichare configured to abut, or be positioned closely adjacent to, sidesurfaces 227 of drive bar 226. Similarly, surfaces 254 and 256 of slot252 and surfaces 266 and 268 of slot 264 can also support the drive bar.While these features are particularly advantageous when used with curvedend-effectors, they can also be used in linear end-effectors. In theseembodiments, even though the slots may be linear, the slots can supportthe driver, whether rigid or flexible, and prevent it from buckling inthe event that it is overloaded, for example.

Although flexible drive bar 226 can be used to advance linear cuttingmember 120 and linear staple driver 130 within a curved end-effector, asdescribed above, flexible drive bar 226 can also be used to advancecurved cutting members and staple drivers, such as cutting member 220and staple driver 230, for example, within a curved end-effector.Furthermore, although not illustrated, one of the anvil and staplecartridge can include a slot configured to receive and guide the cuttingmember and the other of the anvil and staple cartridge can include aslot configured to receive and support the drive bar. In theseembodiments, the slot which is configured to receive the cutting membercan have a different geometry than the slot which is configured toreceive the drive bar. Accordingly, the cutting member and the drive barcan have different thicknesses, for example.

In various embodiments, the support surfaces of slots 248, 264 and 252may be continuous, i.e., they may be configured to contact drive bar 226continuously along the length thereof, or, alternatively, slots 248, 264and 252 may be configured to contact drive bar 226 at various,spaced-apart locations. In these embodiments, projections may extendfrom the slot walls to define the path of the cutting member and thedrive bar. In various embodiments, drive bar 226 may be comprised of aflexible, unitary material such as plastic, for example. Alternatively,referring to FIGS. 25 and 26, drive bar 226 may be comprised of alaminated material, i.e., a material comprised of two or more materialsbonded together. In these embodiments, two or more strips of materialmay be glued together where the strips have the same cross-sectionalgeometry, or, alternatively, different cross-sectional geometries.Furthermore, the strips may be comprised of the same material ordifferent materials. The cross-sectional geometries and materials of theabove-described embodiments may be selected such that the drive bar ismore flexible when deflected in one direction and less flexible whendeflected in a different direction.

As described above, the curvature of an end-effector can be selectedsuch that it facilitates the placement of the end-effector in aparticular surgical site. In various embodiments, referring to FIGS.35-37 and 38-40, the end-effector can be curved in a downward or upwarddirection, i.e., it can be curved in a plane that is substantiallyparallel to planes defined by the staple lines. More particularly,referring to FIGS. 38 and 39, staple cavities 803, which are configuredto store staples 132 therein, are positioned along staple lines 805 and807, for example, such that staples 132, when they are deployed fromstaple cartridge 812, are deployed in substantially parallel planeswhich are at least partially defined by staple lines 805 and 807.

For each parallel plane described above, as a result of these upwardand/or downward curvatures, staples 132 can be deployed along axes whichare co-planar, but not parallel. More particularly, referring to FIG.39, a first staple 132 (not illustrated in FIG. 39) can be deployed fromits staple cavity 803 along axis 853 and a second staple 132 can bedeployed from its staple cavity 803 along axis 855. While axis 853 andaxis 855 can be co-planar, as illustrated in FIG. 39, axis 853 and axis855 are not parallel. In some embodiments, the axes defined by staplecavities 803 can converge, as illustrated in FIGS. 38 and 39, ordiverge, as illustrated in FIGS. 35-37. In various embodiments, thestaple deployment axes can define an angle therebetween which is greaterthan or equal to 30 degrees. In other various embodiments, the axes canbe substantially perpendicular and, in further embodiments, the axes candefine an angle that is greater than ninety degrees.

As described above, an endocutter in accordance with an embodiment ofthe present invention can include a cutting member which is advancedthrough and guided by curved slots in the staple cartridge and/or anvil.For example, referring to FIGS. 38-43, staple cartridge 812 can includeslot 864 which is configured to receive and guide cutting member 120.Similar to the above, endocutter 800 can further include a drive bar foradvancing cutting member 120 within slot 864 of staple cartridge 812,however, owing to the direction and degree of the curvature of staplecartridge 812, some drive bars may be largely unsuitable for use withendocutter 700 or 800, for example. More particularly, the illustrateddrive bars 126 and 226 in FIGS. 4 and 24, respectively, owing to theircross-sectional geometries, may not be particularly well-suited to flexin a substantially downward or substantially upward direction asrequired by endocutters 700 and 800, respectively. Referring to FIG. 26,for example, the illustrated cross-section of drive bar 226 issubstantially rectangular and is defined by height 257 and width 259. Asillustrated in FIG. 26, height 257 is substantially greater than width259 and, as a result, the cross-section of the illustrated drive bar 226has a moment of inertia with respect to height 257 that is substantiallygreater than the moment of inertia with respect to width 259.Accordingly, the illustrated drive bar 226 is substantially lessflexible with respect to height 257 than width 259 and may not be ableto sufficiently bend in the substantially downward and upward directionsdescribed above. It is important to note that drive bars 126 and 226 arenot limited to the configurations described above. On the contrary,drive bars 126 and 226 can have cross-sections in which the width isgreater than the height. Any reference in this paragraph to drive bars126 and 226 are references to the particular drive bars 126 and 226 thathappen to be illustrated in FIGS. 4 and 24, respectively.

Referring to FIGS. 41-43, endocutter 800 can include drive bar 826which, similar to drive bar 226, is configured to advance cutting member120, or a curved cutting member, through curved slots in anend-effector. In various embodiments, drive bar 826 can include across-sectional geometry having a width 859 that is greater than itsheight 857. In these embodiments, the moment of inertia of thecross-section with respect to height 857 is less than the moment ofinertia with respect to width 859. As a result, drive bar 826 can bemore flexible with respect to height 857, i.e., in the upward anddownward directions, than with respect to width 859. In at least oneembodiment, width 859 can be approximately 0.12″ and height 857 can beapproximately 0.05″. Although drive bar 826 is illustrated as having arectangular cross-section, the invention is not so limited. On thecontrary, the cross-section of drive bar 826 can include variousembodiments in which the width of the drive bar cross-section is greaterthan its height. In at least one embodiment, drive bar 826 can include across-section defined by a width and a height wherein the width isgreater than the height, and wherein the width defines an axis that isnot parallel to an axis defined by cutting edge 124 of cutting member120. In various embodiments, as known in the art, cutting edge 124 caninclude a knife edge or a wire configured to conduct currenttherethrough. Furthermore, in various embodiments, the drive bar can beasymmetric with respect to centerline 224 of the distal end of shaft116, for example. In these embodiments, as a result, drive bar 826 canbe predisposed to bending in a pre-determined direction.

Similar to drive bar 226, drive bar 826 can be comprised of one materialor, alternatively, several layers of material bonded together. As above,the flexibility of drive bar 826 can be pre-determined by the types ofmaterials used and the arrangement of the layers within the drive bar.Referring to FIG. 41, cutting member body 822 can include slot 869 whichis configured to receive the distal end of drive bar 826. In the presentembodiment, slot 869 is configured to receive drive bar 826 in apress-fit relationship, however, other means, such as adhesive orfasteners, can be used to secure drive bar 826 to cutting member 820.Similar to the above, staple cartridge 812 can include a slot configuredto receive and support drive bar 826 when it enters into staplecartridge 812. In various embodiments, although not illustrated, anvil834 could be configured to receive and support drive bar 826.

As described above, the jaws of an endocutter can be placed on oppositesides of several layers of tissue, for example, and then closed onto thetissue. In the illustrated embodiments, referring to FIG. 4, jaw 108 canbe pivoted between opened and closed positions with respect to jaw 110via the interaction of inner portion 114 and outer sleeve 116 of shaft106 in a known manner. Although not illustrated, jaw 108 is connected tojaw 110 via a pivot connection such that when inner portion 114 movesjaw 108 relative to outer sleeve 116, jaw 108 is pivoted toward jaw 110.Throughout the movement of jaw 108, the proximal portion of jaw 108,i.e., proximal portion 111, is positioned closer to jaw 110 than itsdistal portion, i.e., distal portion 113, until jaw 108 is brought intoits final position opposite staple cartridge 112. In this final, closedposition, distal portion 113 and proximal portion 111 can besubstantially equidistant from staple cartridge 112. However, as aresult of distal portion 113 being the last portion of jaw 108 to reachits final position, a portion of the tissue, or an artery, for example,can escape from between jaws 108 and 110 before distal portion 113 ismoved into its final position. Accordingly, the surgeon may have toreopen the jaws and reposition the end-effector in an attempt toproperly capture the tissue, or artery, therebetween.

As detailed below, an end-effector in accordance with an embodiment ofthe present invention can be configured to capture the tissue, or anartery, between the distal and proximal portions of the end-effectorbefore the jaws are moved into their final position. In at least oneembodiment, referring to FIGS. 27-34, jaw 608 can be pivotally connectedto jaw 610 via pivot connection 609. Pivot connection 609 can includefirst trunnion 615 and second trunnion 617 extending from jaw 608, and,in addition, first slot 619 and second slot 621 in jaw 610. Trunnions615 and 617 can be sized and configured to fit within slots 619 and 621,respectively, such that pivot connection 609 allows for relativerotational and translation movement between jaw 608 and jaw 610. Inother alternative embodiments, jaw 608 may include slots 619 and 621 andjaw 610 may include trunnions 615 and 617, or any other combinationthereof

Referring to FIGS. 28, 29 and 31 which schematically illustrate slot 619in solid and slot 621 in dashes, trunnions 615 and 617 are configured totravel within slots 619 and 621, respectively, and define the relativemovement between jaws 608 and 610. In the present embodiment, slots 619and 621 define two different arcuate paths for trunnions 615 and 617.More particularly, referring to FIGS. 33 and 34, slot 619 includes firstportion 623, second portion 625, and intermediate portion 627 extendingtherebetween wherein slot 621 also includes first portion 623 and secondportion 625, however, slot 621 includes an intermediate portion, i.e.,portion 629, which is different than intermediate portion 627. Referringto FIG. 27, as a result of slots 619 and 621 having differentintermediate portions, slots 619 and 621 can cause jaw 608 to tilt, orotherwise move in a non-symmetrical manner, with respect to jaw 610 asit is opened and closed. Advantageously, referring to FIGS. 30 and 32,such an asymmetric motion, or tilting, can allow distal portion 613 ofjaw 608 to be placed in close proximity to staple cartridge 612 beforethe intermediate portion of jaw 608, i.e., portion 631, is moved intoits final position illustrated in FIG. 32. As a result, referring toFIG. 30, an end-effector in accordance with the above can be used tocapture tissue, or an artery, between proximal end 611 and distal end613 before intermediate portion 631 is moved into its final, or closed,position. As a result, the possibility of a portion of the tissue, orartery, escaping from between jaws 608 and 610 is reduced. In additionto the above, the distal ends of jaws 608 and 610 can be brought intoclose opposition to each other in order to grip delicate tissue, forexample, without having to completely close the end-effector.

As outlined above, slots 619 and 621 can define different paths fortrunnions 615 and 617, respectively, when jaw 608 is moved between anopen and a closed position. When jaw 608 is in its open position,referring to FIG. 28, trunnions 615 and 617 are positioned within firstportions 623 of slots 619 and 621. In this position, axis 633, which isdefined by trunnions 615 and 617, is substantially collinear with axis635 defined between first portions 623 of slots 619 and 621. Thereafter,jaw 608 can be moved distally such that trunnions 615 and 617 moveupward through slots 619 and 621. Owing to the asymmetric configurationsof slots 619 and 621, referring to FIG. 27 which illustrates jaw 108 ina partially closed position, trunnion 615 is elevated to a relativelyhigher position with respect to trunnion 617, as evidenced by thetilting of axis 633. In this position, an inner edge of jaw 608, i.e.,edge 639, can be in closer proximity to staple cartridge 612 than anouter edge of jaw 608, i.e., edge 641. Advantageously, as a result,inner edge 639 can be brought into contact against the tissue, or anartery, for example, allowing the surgeon to evaluate the position ofthe end-effector with respect to the tissue, or artery, without havingto bring the entire anvil 634 of jaw 608 against the tissue. Thisfeature may be particularly advantageous when the end-effector ispositioned around a pulmonary artery as pulmonary arteries areespecially susceptible to rupture.

After the tissue, or artery, has been captured between the proximal anddistal ends of the end-effector, referring to FIGS. 31 and 32, jaw 608can be moved into its final, or closed, position with respect to staplecartridge 612. In this position, axis 633, which is defined by trunnions615 and 617, can be substantially collinear with axis 637 definedbetween second portions 625 of slots 619 and 621. Furthermore, in thisfinal position, intermediate portion 631, distal portion 613 andproximal portion 611 can be equidistant from staple cartridge 612.Similarly, outer edge 641 and inner edge 639 can also be positionedequidistant with respect to staple cartridge 612. In this finalposition, tissue, or an artery, for example, can be securely retainedbetween jaws 608 and 610. Although the above-described embodimentsinclude a curved end-effector, the invention is not so limited. On thecontrary, the above features can be utilized with a linear end-effector,for example, to achieve the advantages described above.

In various embodiments, slots 619 and 621 can define paths havingdifferent centerlines wherein each centerline can be defined as the lineequidistant from the top and bottom surfaces of each slot. For example,referring to FIGS. 33 and 34, slot 619 can include bottom surface 642and top surface 643 which define a centerline therebetween that isdifferent than the centerline defined by bottom surface 645 and topsurface 647 of slot 621. In these embodiments, slots 619 and 621 can beconfigured to closely retain trunnions 615 and 617 between these top andbottom surfaces such that axis 633 of trunnions 615 and 617substantially travels along the centerlines of slots 619 and 621. Invarious embodiments, jaws 608 and 610 can be configured such thattrunnions 615 and 617 contact bottom surfaces 642 and 645 of slots 619and 621. In these embodiments, jaw 608 can be biased by a spring, forexample, such that trunnions 615 and 617 are positioned against bottomsurfaces 642 and 645 throughout the movement of jaw 608. Owing todifferent profiles for bottom surfaces 642 and 645, the advantagesdescribed above can be achieved.

As described above, once the jaws of the end-effector are closed ontothe layers of tissue, for example, staples can be deployed into thetissue. However, oftentimes, the layers of tissue are very thin and thestaples may not properly capture the tissue therein. To ameliorate thisproblem, as known in the art, buttress material can be placed on one orboth sides of the tissue to support the tissue as it is being stapled.In such embodiments, the purchase of the staples is improved and theclamping force of the staples may be spread more evenly across thebuttress material. In various embodiments, the buttress material can becomprised of a bioabsorbable material such that it can dissolve awayduring the healing process. Previously, however, the buttress materialhas been provided in linear strips which are configured to accommodatelinear staple lines and end-effectors. Such linear strips may beunsuitable for use with endocutters having a curved end-effectorconfigured to deploy staples in curved staple lines.

In accordance with an embodiment of the present invention, referring toFIGS. 44-47, curved staple cartridge 912 can be configured to receive acurved piece, or pieces, of buttress material thereon, such as buttressmaterial 971. Curved buttress material 971 can include inner edge 973which can be configured to substantially parallel the inner radius ofcurvature of jaw 910, and, in addition, outer edge 975 which can beconfigured to substantially parallel the outer radius of curvature ofjaw 910. In some embodiments, referring to FIG. 47, staple cartridge 912can include lip 977 extending therefrom which is configured to retainbuttress material 971 on staple cartridge 912. More particularly, lip977, as illustrated, can be configured to limit lateral movement ofbuttress material 971 with respect to staple cartridge 912 and, althoughnot illustrated, lip 977 can also be configured to extend distal toand/or proximal to the ends of the buttress material to limit relativeaxial movement between buttress material 977 and staple cartridge 912.Similar to the above, curved anvil 934 can be configured to receive apiece, or pieces, of curved buttress material thereon, such as buttressmaterial 979 and 981, for example. Referring to FIG. 47, anvil 934 caninclude several lips 982 which are configured to limit relative movementbetween buttress material 979 and 981 and anvil 934. In variousembodiments, an adhesive, such as cyanoacrylate, for example, can beapplied to the buttress material, anvil and/or staple cartridge tofurther limit the movement of the buttress material or otherwise preventthe mobilization thereof.

As a result of the above, a surgeon may be able to position theend-effector into a surgical site without the buttress material fallingoff or moving relative to the staple cartridge and/or anvil. Oncepositioned, cutting member 120 can be advanced to cut buttress material971. More specifically, referring to FIG. 47, cutting edge 924 can bealigned with buttress material 971 such that it cuts the buttressmaterial as cutting member 920 is advanced through staple cartridge 912.However, in some circumstances, the cutting member may at leastpartially dislodge the buttress material relative to the staplecartridge. This relative movement may especially occur when the buttressmaterial is thick, or, the cutting member must cut more than one pieceof buttress material at a time. To ameliorate this problem, the buttressmaterial may include a series of perforations, for example, positionedalong the path in which the cutting member will cut the buttressmaterial. In these embodiments, these perforations may be formed along aradius of curvature which is parallel to and positioned intermediate twocurved staple rows. In other various embodiments, the buttress materialmay include other features which disrupt the cross-sectional thicknessof the buttress material to facilitate the cutting of the buttressmaterial. As a result of the above, less force may be required to cutthe buttress material and, accordingly, it is less likely the buttressmaterial may slide, for example, when it is cut.

FIGS. 48-50 illustrate another surgical instrument of the presentinvention. As can be seen in these Figures, the surgical instrument 1000includes an end-effector 1002 that has a first jaw 1008 and a second jaw1010. The second jaw 1010 may comprise a channel 1038 that is configuredto operably support a staple cartridge 1012 therein. Staple cartridge1012 may be removably supported in the channel 1038 or, in variousembodiments, staple cartridge 1012 may form an integral part of thesecond jaw 1010. The surgical instrument 1000 further includes a movableanvil 1034 that may be movably coupled to the lower jaw 1010 in thevarious manners described above or in other manners that are known inthe art.

In the embodiment depicted in FIGS. 48-50, the end effector 1002 has adistal end generally designated as 1040. As can further be seen in thoseFigures, the staple cartridge 1012 has a blunt first tip portion 1088thereon. The first tip portion 1088 may be integrally formed (molded,machined, etc.) on the distal end 1013 of the staple cartridge 1012 orit may comprise a separate piece that may be formed with a cavity 1089(FIG. 50) configured to receive a nose 1083 of a conventional staplecartridge 1012. The first tip portion 1088 can include snap features1090 (FIG. 50) or other suitable retainer portions formed therein toretainingly mate with complementary retention grooves 1084 formed in thenose 1083. In addition, or in the alternative, the first tip portion1088 may be affixed to the cartridge 1012 by adhesive such as, forexample, cyanoacrylates, light-curable acrylics, polyurethanes,silicones, epoxies, and ultra-violet curable adhesives such as HenkelLoctite®. In other embodiments, a combination of snap features andgrooves may be provided in both the staple cartridge 1012 and the firsttip portion 1088. Still other forms of fasteners and fastenerarrangements may be used to affix the first tip portion 1088 to thestaple cartridge 1012. In other embodiments, the first tip portion 1088may be affixed to the channel 1038. As can be seen in FIG. 50, the firsttip portion 1088 has a first upwardly extending curved outer surface.

Similarly, in this embodiment, the anvil 1034 may be equipped with asecond tip portion 1092. The second tip portion 1092 may be integrallyformed (molded, machined, etc.) on the distal end 1085 of the anvil 1034or it may comprise a separate piece that may be formed with a cavity1093 configured to receive an end portion of a conventional anvil 1034with snap features 1094 or other suitable retainer portions formedtherein to retainingly mate with complementary retention grooves 1086formed in distal end 1085. In addition, or in the alternative, thesecond tip portion 1092 may be affixed to the anvil 1034 by adhesivesuch as, for example, cyanoacrylates, light-curable acrylics,polyurethanes, silicones, epoxies, and ultra-violet curable adhesivessuch as Henkel Loctite®. In other embodiments, a combination of snapfeatures and grooves may be provided in both distal end 1085 and thesecond tip portion 1092. Still other forms of fasteners may be used toaffix the second tip portion 1092 to the anvil 1034. As can be seen inFIG. 50, the second tip portion 1092 has a downwardly extendingsubstantially curved outer surface.

In various embodiments, the first tip portion 1088 and the second tipportion 1092 may be fabricated from a variety of different materialsthat may be identical to or different from the materials from which thestaple cartridge 1012 and anvil 1034 are manufactured. For example, thefirst tip portion 1088 and the second tip portion 1092 may bemanufactured from soft plastic, rubber, etc. The first tip portion 1088and the second tip portion 1092 may be fabricated from the same ordifferent materials.

In various embodiments, the first tip portion 1088 and the second tipportion 1092 are shaped such that their respective outer surfaces 1088′,1092′ cooperate to substantially form a substantially blunt end effectornose generally designated as 1096 that, in one exemplary embodiment, hasa paraboloid surface 1098 when the anvil 1034 is in the closed positionas shown in FIG. 50. As used herein, the term “paraboloid surface” meansa surface having parabolic sections parallel to a single coordinate axisand elliptic sections perpendicular to that axis. Those of ordinaryskill in the art will appreciate that when employing various embodimentsof the instrument 1000, as long as the surgeon can see one or the otherof the first tip portion or second tip portion, the surgeon will knowwhere the other tip portion is, even if it is behind tissue or otherstructures. In addition, the unique and novel tip configurations permitthe surgeon to pass the anvil and/or channel around tissue without greatrisk of incidental trauma to adjacent tissues. Furthermore, when in theclosed orientation as depicted in FIGS. 49 and 50, these embodiments areparticularly well suited for use as a dissector for separating andmanipulating tissues.

The first tip portion and the second tip portion have been described anddepicted in the Figures as being used in connection with a curved endeffector. Those of ordinary skill in the art will readily appreciate,however, that the first and second tip portions may be used inconnection with a variety of different end effector configurations suchas linear endocutters and other types of end effectors without departingfrom the spirit and scope of the present invention. Thus, the first andsecond tip portions described above should not be limited solely to usein connection with curved endocutters/staplers.

As was described above, the first tip portion may be constructed forattachment to the distal end of a conventional staple cartridge or itmay be integrally formed on the end of the staple cartridge. In stillother embodiments, the first tip portion may be constructed forattachment to a distal end of the channel or it may be integrally formedon the distal end of the channel. Similarly, the second tip portion maybe constructed for attachment to a conventional endocutter anvil or itmay be integrally formed on the distal end of the anvil. In thoseapplications wherein the first tip portion and/or second tip portion arefabricated separately from the cartridge and anvil, respectively, thetip portions may be supplied as a kit for retrofitting onto thecartridge and anvil by the end user. For example, in such arrangements,the tip portions may be presterilized and packaged and be configured tosnap onto or otherwise attach to the staple cartridge and anvil orchannel and anvil, whichever the case may be.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

Preferably, the invention described herein will be processed beforesurgery. First, a new or used instrument is obtained and if necessarycleaned. The instrument can then be sterilized. In one sterilizationtechnique, the instrument is placed in a closed and sealed container,such as a plastic or TYVEK bag. The container and instrument are thenplaced in a field of radiation that can penetrate the container, such asgamma radiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

What is claimed is:
 1. A surgical stapler, comprising: a staplecartridge, comprising: a curved deck configured to support tissuecomprising: an inner radius of curvature; an outer radius of curvature;a first step; and a second step, wherein said first step is taller thansaid second step, and wherein said second step is positioned laterallyand inwardly with respect to said first step; a first longitudinal rowof staple cavities defined in said first step; a second longitudinal rowof staple cavities defined in said second step; and staples removablystored in said first and second longitudinal rows of staple cavities; ananvil configured to deform said staples; a first camming member; asecond camming member, wherein said first camming member and said secondcamming member are configured to control the relative position of saidstaple cartridge and said anvil; a cutting member having a cuttingsurface, wherein said cutting member is relatively movable with respectto said anvil and said staple cartridge; a driver operably engaged withsaid cutting member to move said cutting member relative to said anviland said staple cartridge; and support means for supporting said driverwhen said driver moves said cutting member relative to said anvil andsaid staple cartridge.
 2. The surgical stapler of claim 1, wherein saidsupport means also guides said cutting member as said cutting member ismoved relative to said anvil and said staple cartridge.
 3. The surgicalstapler of claim 1, wherein said support means includes a curved slot inone of said anvil and said staple cartridge, and wherein said curvedslot is configured to receive at least a portion of said driver.
 4. Thesurgical stapler of claim 3, wherein said support means further includesa second slot in the other of said anvil and said staple cartridge, andwherein said second slot is configured to receive at least a portion ofsaid driver.
 5. The surgical stapler of claim 3, wherein said curvedslot includes a first surface and a second surface, and wherein saidcurved slot further includes first projections extending from said firstsurface and second projections extending from said second surface, saidfirst projections and said second projections defining a curved path forsaid cutting member and said driver.
 6. The surgical stapler of claim 1,wherein said driver is comprised of at least two layers of materialbonded together.
 7. The surgical stapler of claim 1, wherein said firstcamming member and said second camming member are configured toco-operatively set a tissue gap distance between the staple cartridgeand said anvil.
 8. The surgical stapler of claim 1, wherein at least aportion of said driver is deformable to match at least one of said innerradius of curvature or said outer radius of curvature.